%0 Journal Article %A Babuška, Ivo %T Computation of derivatives in the finite element method %J Commentationes Mathematicae Universitatis Carolinae %D 1970 %P 545-558 %V 11 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMUC_1970__11_3_a10/ %G en %F CMUC_1970__11_3_a10